TAMPA — When uniformed police showed up at Ocean Spa Massage, several women ran out the back door.Tampa police believe those women were victims of human trafficking.On Thursday, the agency returned to the South Tampa business with a search warrant in hand. Inside, they found three adult women. Two spoke only Korean, so a translator from MacDill Air Force Base helped.The women were not cooperative, and police do not believe they are licensed massage therapists."This is not a legitimate business," police Chief Jane Castor said at a news conference outside the bright purple building, at 3631 Henderson Blvd.The officers had already seen the adult websites advertising the business: private parking and "very kind caring nurturing Asian hands," one site states. On another, anonymous writers give reviews of the sexual acts they participated in at Ocean Spa.Kathy Cusmano, who works next door, says she often saw men park behind the business. It was common knowledge in the area that the spa was not legitimate, she said.The three women interviewed Thursday were not immediately arrested, and police did not release their names.It is unclear where the young women previously seen at the business were on Thursday, Castor said.Inside the spa, police found multiple rooms, showers and a kitchen with a refrigerator and food. There were also mattresses in the back — an indicator that people are living in the business, police said.Authorities say that massage businesses are sometimes the sites of human trafficking and prostitution. Often, these workers do not have massage therapy licenses. State officials, along with the Florida State Massage Therapy Association, have been working to combat this crime through legislation and by taking away licenses from people who obtained them fraudulently.This investigation started with an anonymous tip to Crime Stoppers in October.Undercover police officers twice went to Ocean Spa and were offered sex acts for money, Castor said.A Florida Department of Health inspection in late 2012 discovered multiple mattresses and personal belongings in a back room."We're trying to get to the bottom of where (these women) came from and why they're here," Castor said. "We're continuing the investigation."Times news researcher John Martin contributed to this report.